With this enhancement, mkeficapsule will be able to sign a capsule
file when it is created. A signature added will be used later
in the verification at FMP's SetImage() call.

To do that, We need specify additional command parameters:
  -monotonic-cout <count> : monotonic count
  -private-key <private key file> : private key file
  -certificate <certificate file> : certificate file
Only when all of those parameters are given, a signature will be added
to a capsule file.

Users are expected to maintain and increment the monotonic count at
every time of the update for each firmware image.

Signed-off-by: AKASHI Takahiro <takahiro.aka...@linaro.org>
Reviewed-by: Simon Glass <s...@chromium.org>
---
 tools/Kconfig        |   8 +
 tools/Makefile       |   8 +-
 tools/mkeficapsule.c | 382 ++++++++++++++++++++++++++++++++++++++++---
 3 files changed, 376 insertions(+), 22 deletions(-)

diff --git a/tools/Kconfig b/tools/Kconfig
index 91ce8ae3e516..117c921da3fe 100644
--- a/tools/Kconfig
+++ b/tools/Kconfig
@@ -90,4 +90,12 @@ config TOOLS_SHA512
        help
          Enable SHA512 support in the tools builds
 
+config TOOLS_MKEFICAPSULE
+       bool "Build efimkcapsule command"
+       default y if EFI_CAPSULE_ON_DISK
+       help
+         This command allows users to create a UEFI capsule file and,
+         optionally sign that file. If you want to enable UEFI capsule
+         update feature on your target, you certainly need this.
+
 endmenu
diff --git a/tools/Makefile b/tools/Makefile
index b45219e2c30c..5a73cc4b363d 100644
--- a/tools/Makefile
+++ b/tools/Makefile
@@ -238,8 +238,12 @@ hostprogs-$(CONFIG_MIPS) += mips-relocs
 hostprogs-$(CONFIG_ASN1_COMPILER)      += asn1_compiler
 HOSTCFLAGS_asn1_compiler.o = -idirafter $(srctree)/include
 
-mkeficapsule-objs      := mkeficapsule.o $(LIBFDT_OBJS)
-hostprogs-$(CONFIG_EFI_HAVE_CAPSULE_SUPPORT) += mkeficapsule
+HOSTLDLIBS_mkeficapsule += -luuid
+ifeq ($(CONFIG_TOOLS_LIBCRYPTO),y)
+HOSTLDLIBS_mkeficapsule += \
+       $(shell pkg-config --libs libssl libcrypto 2> /dev/null || echo "-lssl 
-lcrypto")
+endif
+hostprogs-$(CONFIG_TOOLS_MKEFICAPSULE) += mkeficapsule
 
 # We build some files with extra pedantic flags to try to minimize things
 # that won't build on some weird host compiler -- though there are lots of
diff --git a/tools/mkeficapsule.c b/tools/mkeficapsule.c
index 8427fedd941c..086757ee8ad7 100644
--- a/tools/mkeficapsule.c
+++ b/tools/mkeficapsule.c
@@ -15,6 +15,16 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 
+#include <linux/kconfig.h>
+#ifdef CONFIG_TOOLS_LIBCRYPTO
+#include <openssl/asn1.h>
+#include <openssl/bio.h>
+#include <openssl/evp.h>
+#include <openssl/err.h>
+#include <openssl/pem.h>
+#include <openssl/pkcs7.h>
+#endif
+
 typedef __u8 u8;
 typedef __u16 u16;
 typedef __u32 u32;
@@ -38,12 +48,25 @@ efi_guid_t efi_guid_image_type_uboot_fit =
                EFI_FIRMWARE_IMAGE_TYPE_UBOOT_FIT_GUID;
 efi_guid_t efi_guid_image_type_uboot_raw =
                EFI_FIRMWARE_IMAGE_TYPE_UBOOT_RAW_GUID;
+efi_guid_t efi_guid_cert_type_pkcs7 = EFI_CERT_TYPE_PKCS7_GUID;
+
+#ifdef CONFIG_TOOLS_LIBCRYPTO
+static const char *opts_short = "f:r:i:I:v:p:c:m:dh";
+#else
+static const char *opts_short = "f:r:i:I:v:h";
+#endif
 
 static struct option options[] = {
        {"fit", required_argument, NULL, 'f'},
        {"raw", required_argument, NULL, 'r'},
        {"index", required_argument, NULL, 'i'},
        {"instance", required_argument, NULL, 'I'},
+#ifdef CONFIG_TOOLS_LIBCRYPTO
+       {"private-key", required_argument, NULL, 'p'},
+       {"certificate", required_argument, NULL, 'c'},
+       {"monotonic-count", required_argument, NULL, 'm'},
+       {"dump-sig", no_argument, NULL, 'd'},
+#endif
        {"help", no_argument, NULL, 'h'},
        {NULL, 0, NULL, 0},
 };
@@ -57,10 +80,252 @@ static void print_usage(void)
               "\t-r, --raw <raw image>       new raw image file\n"
               "\t-i, --index <index>         update image index\n"
               "\t-I, --instance <instance>   update hardware instance\n"
+#ifdef CONFIG_TOOLS_LIBCRYPTO
+              "\t-p, --private-key <privkey file>  private key file\n"
+              "\t-c, --certificate <cert file>     signer's certificate file\n"
+              "\t-m, --monotonic-count <count>     monotonic count\n"
+              "\t-d, --dump_sig              dump signature (*.p7)\n"
+#endif
               "\t-h, --help                  print a help message\n",
               tool_name);
 }
 
+/**
+ * auth_context - authentication context
+ * @key_file:  Path to a private key file
+ * @cert_file: Path to a certificate file
+ * @image_data:        Pointer to firmware data
+ * @image_size:        Size of firmware data
+ * @auth:      Authentication header
+ * @sig_data:  Signature data
+ * @sig_size:  Size of signature data
+ *
+ * Data structure used in create_auth_data(). @key_file through
+ * @image_size are input parameters. @auth, @sig_data and @sig_size
+ * are filled in by create_auth_data().
+ */
+struct auth_context {
+       char *key_file;
+       char *cert_file;
+       u8 *image_data;
+       size_t image_size;
+       struct efi_firmware_image_authentication auth;
+       u8 *sig_data;
+       size_t sig_size;
+};
+
+static int dump_sig;
+
+#ifdef CONFIG_TOOLS_LIBCRYPTO
+/**
+ * fileio-read_pkey - read out a private key
+ * @filename:  Path to a private key file
+ *
+ * Read out a private key file and parse it into "EVP_PKEY" structure.
+ *
+ * Return:
+ * * Pointer to private key structure  - on success
+ * * NULL - on failure
+ */
+static EVP_PKEY *fileio_read_pkey(const char *filename)
+{
+       EVP_PKEY *key = NULL;
+       BIO *bio;
+
+       bio = BIO_new_file(filename, "r");
+       if (!bio)
+               goto out;
+
+       key = PEM_read_bio_PrivateKey(bio, NULL, NULL, NULL);
+
+out:
+       BIO_free_all(bio);
+       if (!key) {
+               printf("Can't load key from file '%s'\n", filename);
+               ERR_print_errors_fp(stderr);
+       }
+
+       return key;
+}
+
+/**
+ * fileio-read_cert - read out a certificate
+ * @filename:  Path to a certificate file
+ *
+ * Read out a certificate file and parse it into "X509" structure.
+ *
+ * Return:
+ * * Pointer to certificate structure  - on success
+ * * NULL - on failure
+ */
+static X509 *fileio_read_cert(const char *filename)
+{
+       X509 *cert = NULL;
+       BIO *bio;
+
+       bio = BIO_new_file(filename, "r");
+       if (!bio)
+               goto out;
+
+       cert = PEM_read_bio_X509(bio, NULL, NULL, NULL);
+
+out:
+       BIO_free_all(bio);
+       if (!cert) {
+               printf("Can't load certificate from file '%s'\n", filename);
+               ERR_print_errors_fp(stderr);
+       }
+
+       return cert;
+}
+
+/**
+ * create_auth_data - compose authentication data in capsule
+ * @auth_context:      Pointer to authentication context
+ *
+ * Fill up an authentication header (.auth) and signature data (.sig_data)
+ * in @auth_context, using library functions from openssl.
+ * All the parameters in @auth_context must be filled in by a caller.
+ *
+ * Return:
+ * * 0  - on success
+ * * -1 - on failure
+ */
+static int create_auth_data(struct auth_context *ctx)
+{
+       EVP_PKEY *key = NULL;
+       X509 *cert = NULL;
+       BIO *data_bio = NULL;
+       const EVP_MD *md;
+       PKCS7 *p7;
+       int flags, ret = -1;
+
+       OpenSSL_add_all_digests();
+       OpenSSL_add_all_ciphers();
+       ERR_load_crypto_strings();
+
+       key = fileio_read_pkey(ctx->key_file);
+       if (!key)
+               goto err;
+       cert = fileio_read_cert(ctx->cert_file);
+       if (!cert)
+               goto err;
+
+       /*
+        * create a BIO, containing:
+        *  * firmware image
+        *  * monotonic count
+        * in this order!
+        * See EDK2's FmpAuthenticatedHandlerRsa2048Sha256()
+        */
+       data_bio = BIO_new(BIO_s_mem());
+       BIO_write(data_bio, ctx->image_data, ctx->image_size);
+       BIO_write(data_bio, &ctx->auth.monotonic_count,
+                 sizeof(ctx->auth.monotonic_count));
+
+       md = EVP_get_digestbyname("SHA256");
+       if (!md)
+               goto err;
+
+       /* create signature */
+       /* TODO: maybe add PKCS7_NOATTR and PKCS7_NOSMIMECAP */
+       flags = PKCS7_BINARY | PKCS7_DETACHED;
+       p7 = PKCS7_sign(NULL, NULL, NULL, data_bio, flags | PKCS7_PARTIAL);
+       if (!p7)
+               goto err;
+       if (!PKCS7_sign_add_signer(p7, cert, key, md, flags))
+               goto err;
+       if (!PKCS7_final(p7, data_bio, flags))
+               goto err;
+
+       /* convert pkcs7 into DER */
+       ctx->sig_data = NULL;
+       ctx->sig_size = ASN1_item_i2d((ASN1_VALUE *)p7, &ctx->sig_data,
+                                     ASN1_ITEM_rptr(PKCS7));
+       if (!ctx->sig_size)
+               goto err;
+
+       /* fill auth_info */
+       ctx->auth.auth_info.hdr.dwLength = sizeof(ctx->auth.auth_info)
+                                               + ctx->sig_size;
+       ctx->auth.auth_info.hdr.wRevision = WIN_CERT_REVISION_2_0;
+       ctx->auth.auth_info.hdr.wCertificateType = WIN_CERT_TYPE_EFI_GUID;
+       memcpy(&ctx->auth.auth_info.cert_type, &efi_guid_cert_type_pkcs7,
+              sizeof(efi_guid_cert_type_pkcs7));
+
+       ret = 0;
+err:
+       BIO_free_all(data_bio);
+       EVP_PKEY_free(key);
+       X509_free(cert);
+
+       return ret;
+}
+
+/**
+ * dump_signature - dump out a signature
+ * @path:      Path to a capsule file
+ * @signature: Signature data
+ * @sig_size:  Size of signature data
+ *
+ * Signature data pointed to by @signature will be saved into
+ * a file whose file name is @path with ".p7" suffix.
+ *
+ * Return:
+ * * 0  - on success
+ * * -1 - on failure
+ */
+static int dump_signature(const char *path, u8 *signature, size_t sig_size)
+{
+       char *sig_path;
+       FILE *f;
+       size_t size;
+       int ret = -1;
+
+       sig_path = malloc(strlen(path) + 3 + 1);
+       if (!sig_path)
+               return ret;
+
+       sprintf(sig_path, "%s.p7", path);
+       f = fopen(sig_path, "w");
+       if (!f)
+               goto err;
+
+       size = fwrite(signature, 1, sig_size, f);
+       if (size == sig_size)
+               ret = 0;
+
+       fclose(f);
+err:
+       free(sig_path);
+       return ret;
+}
+
+/**
+ * free_sig_data - free out signature data
+ * @ctx:       Pointer to authentication context
+ *
+ * Free signature data allocated in create_auth_data().
+ */
+static void free_sig_data(struct auth_context *ctx)
+{
+       if (ctx->sig_size)
+               OPENSSL_free(ctx->sig_data);
+}
+#else
+static int create_auth_data(struct auth_context *ctx)
+{
+       return 0;
+}
+
+static int dump_signature(const char *path, u8 *signature, size_t sig_size)
+{
+       return 0;
+}
+
+static void free_sig_data(struct auth_context *ctx) {}
+#endif
+
 /**
  * read_bin_file - read a firmware binary file
  * @bin:       Path to a firmware binary file
@@ -162,11 +427,13 @@ static int write_capsule_file(FILE *f, void *data, size_t 
size, const char *msg)
  * * -1 - on failure
  */
 static int create_fwbin(char *path, char *bin, efi_guid_t *guid,
-                       unsigned long index, unsigned long instance)
+                       unsigned long index, unsigned long instance,
+                       uint64_t mcount, char *privkey_file, char *cert_file)
 {
        struct efi_capsule_header header;
        struct efi_firmware_management_capsule_header capsule;
        struct efi_firmware_management_capsule_image_header image;
+       struct auth_context auth_context;
        FILE *f;
        void *data;
        off_t bin_size;
@@ -176,9 +443,9 @@ static int create_fwbin(char *path, char *bin, efi_guid_t 
*guid,
 #ifdef DEBUG
        printf("For output: %s\n", path);
        printf("\tbin: %s\n\ttype: %pUl\n", bin, guid);
-       printf("\tindex: %ld\n\tinstance: %ld\n", index, instance);
+       printf("\tindex: %lu\n\tinstance: %lu\n", index, instance);
 #endif
-
+       auth_context.sig_size = 0;
        f = NULL;
        data = NULL;
        ret = -1;
@@ -189,6 +456,27 @@ static int create_fwbin(char *path, char *bin, efi_guid_t 
*guid,
        if (read_bin_file(bin, &data, &bin_size))
                goto err;
 
+       /* first, calculate signature to determine its size */
+       if (privkey_file && cert_file) {
+               auth_context.key_file = privkey_file;
+               auth_context.cert_file = cert_file;
+               auth_context.auth.monotonic_count = mcount;
+               auth_context.image_data = data;
+               auth_context.image_size = bin_size;
+
+               if (create_auth_data(&auth_context)) {
+                       printf("Signing firmware image failed\n");
+                       goto err;
+               }
+
+               if (dump_sig &&
+                   dump_signature(path, auth_context.sig_data,
+                                  auth_context.sig_size)) {
+                       printf("Creating signature file failed\n");
+                       goto err;
+               }
+       }
+
        /*
         * write a capsule file
         */
@@ -209,6 +497,9 @@ static int create_fwbin(char *path, char *bin, efi_guid_t 
*guid,
                                        + sizeof(capsule) + sizeof(u64)
                                        + sizeof(image)
                                        + bin_size;
+       if (auth_context.sig_size)
+               header.capsule_image_size += sizeof(auth_context.auth)
+                               + auth_context.sig_size;
        if (write_capsule_file(f, &header, sizeof(header),
                               "Capsule header"))
                goto err;
@@ -239,13 +530,32 @@ static int create_fwbin(char *path, char *bin, efi_guid_t 
*guid,
        image.reserved[1] = 0;
        image.reserved[2] = 0;
        image.update_image_size = bin_size;
+       if (auth_context.sig_size)
+               image.update_image_size += sizeof(auth_context.auth)
+                               + auth_context.sig_size;
        image.update_vendor_code_size = 0; /* none */
        image.update_hardware_instance = instance;
        image.image_capsule_support = 0;
+       if (auth_context.sig_size)
+               image.image_capsule_support |= CAPSULE_SUPPORT_AUTHENTICATION;
        if (write_capsule_file(f, &image, sizeof(image),
                               "Firmware capsule image header"))
                goto err;
 
+       /*
+        * signature
+        */
+       if (auth_context.sig_size) {
+               if (write_capsule_file(f, &auth_context.auth,
+                                      sizeof(auth_context.auth),
+                                      "Authentication header"))
+                       goto err;
+
+               if (write_capsule_file(f, auth_context.sig_data,
+                                      auth_context.sig_size, "Signature"))
+                       goto err;
+       }
+
        /*
         * firmware binary
         */
@@ -262,23 +572,37 @@ err:
        return ret;
 }
 
-/*
- * Usage:
- *   $ mkeficapsule -f <firmware binary> <output file>
+/**
+ * main - main entry function of mkeficapsule
+ * @argc:      Number of arguments
+ * @argv:      Array of pointers to arguments
+ *
+ * Create an uefi capsule file, optionally signing it.
+ * Parse all the arguments and pass them on to create_fwbin().
+ *
+ * Return:
+ * * 0  - on success
+ * * -1 - on failure
  */
 int main(int argc, char **argv)
 {
        char *file;
        efi_guid_t *guid;
        unsigned long index, instance;
+       uint64_t mcount;
+       char *privkey_file, *cert_file;
        int c, idx;
 
        file = NULL;
        guid = NULL;
        index = 0;
        instance = 0;
+       mcount = 0;
+       privkey_file = NULL;
+       cert_file = NULL;
+       dump_sig = 0;
        for (;;) {
-               c = getopt_long(argc, argv, "f:r:i:I:v:h", options, &idx);
+               c = getopt_long(argc, argv, opts_short, options, &idx);
                if (c == -1)
                        break;
 
@@ -286,7 +610,7 @@ int main(int argc, char **argv)
                case 'f':
                        if (file) {
                                printf("Image already specified\n");
-                               return -1;
+                               exit(EXIT_FAILURE);
                        }
                        file = optarg;
                        guid = &efi_guid_image_type_uboot_fit;
@@ -294,7 +618,7 @@ int main(int argc, char **argv)
                case 'r':
                        if (file) {
                                printf("Image already specified\n");
-                               return -1;
+                               exit(EXIT_FAILURE);
                        }
                        file = optarg;
                        guid = &efi_guid_image_type_uboot_raw;
@@ -305,26 +629,44 @@ int main(int argc, char **argv)
                case 'I':
                        instance = strtoul(optarg, NULL, 0);
                        break;
+#ifdef CONFIG_TOOLS_LIBCRYPTO
+               case 'p':
+                       if (privkey_file) {
+                               printf("Private Key already specified\n");
+                               exit(EXIT_FAILURE);
+                       }
+                       privkey_file = optarg;
+                       break;
+               case 'c':
+                       if (cert_file) {
+                               printf("Certificate file already specified\n");
+                               exit(EXIT_FAILURE);
+                       }
+                       cert_file = optarg;
+                       break;
+               case 'm':
+                       mcount = strtoul(optarg, NULL, 0);
+                       break;
+               case 'd':
+                       dump_sig = 1;
+                       break;
+#endif /* CONFIG_TOOLS_LIBCRYPTO */
                case 'h':
                        print_usage();
-                       return 0;
+                       exit(EXIT_SUCCESS);
                }
        }
 
-       /* need an output file */
-       if (argc != optind + 1) {
+       /* check necessary parameters */
+       if ((argc != optind + 1) || !file ||
+           ((privkey_file && !cert_file) ||
+            (!privkey_file && cert_file))) {
                print_usage();
                exit(EXIT_FAILURE);
        }
 
-       /* need a fit image file or raw image file */
-       if (!file) {
-               print_usage();
-               exit(EXIT_SUCCESS);
-       }
-
-       if (create_fwbin(argv[optind], file, guid, index, instance)
-                       < 0) {
+       if (create_fwbin(argv[optind], file, guid, index, instance,
+                        mcount, privkey_file, cert_file) < 0) {
                printf("Creating firmware capsule failed\n");
                exit(EXIT_FAILURE);
        }
-- 
2.33.0

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